<h1>Cap-and-trade markets reduce particulate pollution while lowering compliance costs and improving industry compliance.</h1> A cap-and-trade market for particulate emissions in Surat substituted a market-based permit trading system for conventional controls, enabling firms to buy and sell allowances under an overall cap. The pilot yielded greater emission reductions than traditional regulation, sharply reduced non-compliance, lowered firms' compliance costs, and increased profitability. Following pilot results, Gujarat expanded to a second market in Ahmedabad and is developing sulfur-dioxide and wastewater trading schemes for broader replication.